The invention relates to a plug connector consisting of a plug-in jack and a plug part provided for insertion into the plug-in jack. More particularly, the invention relates to a so-called back-panel plug connector in which one of the two plug connector parts is mounted on a back-panel circuit board firmly mounted in a housing of an electrical device, the so-called motherboard, and the other part of the plug connector is mounted on a pluggable circuit board, the so-called plug-in card. When the plug-in card is inserted into the housing, the contacts of the plug-in jack and of the plug part, respectively, engage into the contacts of the other part so that the plug-in card is connected to the motherboard.
There arises a problem in that the plug-in card cannot be guided so precisely in the housing that it can be inserted without any tolerances. This means that the contact pins and the contact jacks are laterally offset with respect to each other and/or may present a false angular position relative to each other in that moment when they hit each other during insertion of the plug-in card, i.e. that their longitudinal axes are out of alignment. The greater part of these alignment errors may certainly be corrected during insertion of the plug part into the plug-in jack; with this correction, however, comparatively high forces act on the contacts of the plug-in jack and the plug part. There is a risk that deformations and stresses on the soldering points of the contacts occur. This is especially critical for SMT connections which, in contrast to through contacts, are not positively connected with the circuit board.
Thus, it is the object underlying the invention to provide a plug connector in which the contacts are not exposed to high mechanical loads during insertion of the plug-in card into the housing and, accordingly, of the plug part into the plug-in jack if there exists some misalignment between the plug part and the plug-in jack.
This is achieved in a plug-in jack comprising an insulating jack housing in which at least one jack contact is accommodated. The jack contact consists of a retaining part and a jack, the jack being mounted on the retaining part so as to be pivotable by a limited angle. The complementary plug part comprises an insulating plug housing in which at least one plug contact is accommodated, which is provided for engaging with the jack of the complementary plug-in jack. Since the jack is mounted so as to be pivotable on the retaining part, misalignments of the plug-in jack and the plug part relative to each other may automatically be compensated for. This prevents high mechanical loads from acting on the contacts.
According to a preferred first embodiment, it is provided that the retaining part of the plug-in jack comprises a head portion, an adjoining annular groove and a collar adjoining the annular groove and that the jack comprises a plurality of spring shackles engaging with the annular groove. On their free ends, the spring shackles preferably comprise hooks engaging with the annular groove. This makes it possible to mount the jack, in a very simple manner, to be pivotable on the retaining part. With its spring shackles, the jack is pushed over the head portion onto the retaining part, the spring shackles elastically widening when sliding over the head portion and subsequently snapping into the annular groove. There, the jack is reliably held by the hooks resting on the shoulder between the annular groove and the head portion while, at the same time, the jack may be pivoted by a certain angle. This angle is given by the difference between the width of the hooks and the width of the annular groove between the collar and the head portion. The higher this difference is, the farther the jack may be pivoted.
The jack is preferably barrel-shaped and is provided with several contact shackles at its end opposite the hook. The contact shackles widen elastically when the plug contact is pushed into the jack. The jack together with the spring shackles and the contact shackles may easily be produced in that a flat sheet stamping part is first provided with incisions so that the contact shackles and the spring shackles are formed, this stamping part then being rolled together to have the desired barrel-like shape.
According to the preferred first embodiment of the invention, the collar of the retaining part of the jack contact is adjoined by an anchor groove followed by an anchor portion accommodated in the jack housing, an annular spring being accommodated in the anchor groove, its edge facing the collar being beveled and the diameter of the collar and the head of the retaining part being less than the diameter of the anchor portion. This configuration makes it possible to assemble and mount the retaining part in the jack housing very easily. At first, the annular spring is pushed onto the anchor groove. Then the retaining part is pushed into an anchor opening in the jack housing from the rear side of the jack housing, the annular spring being elastically compressed when passing through the anchor opening and subsequently adopting its original shape again. Thus, there is formed a snap closure which makes it possible to push the retaining part into the jack housing, but impossible to pull it out in the opposite direction. In a similar manner, the plug contacts of the plug housing are received therein.
According to a preferred second embodiment, it is provided that the retaining part comprises a retaining opening and the jack comprises at least one hook engaging into the retaining opening. Here, it is preferably provided that the retaining part comprises a rectangular cross-section at least in the region of the retaining opening and that the jack is provided with two spring shackles which face each other in parallel and rest on two lateral faces of the retaining part facing away from each other. The hook may be formed by a sheet metal shackle bent from the spring shackle. The jack is reliably retained on the retaining part while the two other spring shackles resting on the retaining part make it possible, due to their elasticity, to pivot the jack in every direction on the retaining part.
It is preferably provided that the jack comprises two contact shackles facing each other in parallel and that the spring shackles face each other along a first direction being at right angles with respect to a second direction where the contact shackles face each other. The differing orientation of the contact shackles and the spring shackles ensures that a restoring force into the normal position is generated each time the jack is displaced from its normal position.
It is preferably provided that the jack is a bent sheet metal part having a closed center portion. Such a bent sheet metal part may be produced at low expenditure by stamping and bending a suitable metal sheet.
Preferably, both the retaining parts of the plug-in jack and the plug contacts of the plug parts each comprise an SMT connection which makes it possible to mount them on a circuit board via a surface mounting technique, favorable from a process engineering point of view.
Advantageous configurations of the invention may be taken from the subclaims.